Update docker.elastic.co/wolfi/chainguard-base:latest Docker digest to 3f6bcf4 (elastic#124013)

This PR contains the following updates:

| Package | Update | Change | |---|---|---| |
docker.elastic.co/wolfi/chainguard-base | digest | `6387bd4` ->
`3f6bcf4` |

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This PR has been generated by [Renovate
Bot](https://redirect.github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzOS4xMDcuMCIsInVwZGF0ZWRJblZlciI6IjM5LjEwNy4wIiwidGFyZ2V0QnJhbmNoIjoiOC4xNiIsImxhYmVscyI6WyI6RGVsaXZlcnkvUGFja2FnaW5nIiwiPm5vbi1pc3N1ZSIsIlRlYW06RGVsaXZlcnkiLCJhdXRvLW1lcmdlLXdpdGhvdXQtYXBwcm92YWwiXX0=-->

Author: elastic-renovate-prod[bot]

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/DockerBase.java

@@ -31,7 +31,7 @@ public enum DockerBase {
     // Chainguard based wolfi image with latest jdk
     // This is usually updated via renovatebot
     // spotless:off
-    WOLFI("docker.elastic.co/wolfi/chainguard-base:latest@sha256:6387bd4c462007eaecaf13a423aea99c8a8452da09244c129703324aa97769c6",
+    WOLFI("docker.elastic.co/wolfi/chainguard-base:latest@sha256:3f6bcf4db22d9809c7e0d7bf02bb2c549f22e3a62d53496901340f2bbe082e2b",
         "-wolfi",
         "apk"
     );